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Home >> Porsche >> 1989 >> 944 S2 L4-2990cc 3.0L DOHC >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Pinpoint Tests >> Test Point 6 - Idle Speed Control
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Test Point 6 - Idle Speed Control

Terminal Identification:





CODE 1_22 - IDLE SPEED CONTROL
1. Disconnect idle speed control electrical connector.
2. Connect voltmeter between harness terminal 2 and ground.
3. Turn ignition on.

Battery voltage, Proceed to next step.
No battery voltage, check wiring. End of test.

4. Install test jumpers between disconnected plug and idle speed control.
5. Start engine and idle.
6. Connect oscilloscope to test jumpers.

Idle Speed Control Scope Pattern:





7. If scope pattern is incorrect, check wiring before replacing DME control unit. If pattern is correct and idle speed control vibrates during operation, control working properly.


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